Blower



-"Sept.-.-;]/3, 193s. o. D. H. BENTL EY 2,129,808

BLOWER Filed Nov. 9, 1937 4 2 Sheets-Sheet l Sept. 13, 1938. o. D. H.BENTLEY BLOWER 2 Sheets-Sheet 2 Filed NOV. 9, 1937 v 1170877367 OLIVERD. H. BENTLEY by @6012 a Patented Sept. 13, 1938 UNITED STATES PATENTOFFICE .Oliver D. H. Bentley, Norfolk, Mass. Application November 9,1937, Serial No. 173,637

4 Claims.

This invention relates to blowers and relates more particularly to acombined propeller and centrifugal blower. V

For some classes of work such for example, as providing air for forceddraft for naval vessels, air pressureslof the order of 16" of water arerequired. In order to provide such pressures in the past, it has beenthe practice to rotate the blower blades at such high speeds that theywere not only very noisy in operation but the strains to which they weresubjected were great.

According to this invention, a propeller type fan rotating in onedirection at a reduced speed, feeds air axially into'the inlet of thewheel, rotating in the opposite direction at a reduced speed, of acentrifugal fan. This results in energy conversion at high efliciencyand provides the desired air pressure at greatly reduced speed.

In one embodiment of the invention, a propeller type fan is mounted inthe inlet of a centrifugal fan. Oppositely revolving rotors of a steamturbine drive the propeller blades and the fan wheel through concentricshafts. The high relative speeds of the turbine rotors result in aneflicient prime mover, while providing the reduced speed desired for thefan rotors. The propeller blades act to super-charge the centrifugalfan, the air from which is discharged through a preferred involutecasing.

An object of the invention is to provide relatively high air pressuresby means of relatively low speed blowers.

Another object of the invention is to supercharge a centrifugal fan witha propeller fan.

Another object of the invention is to supercharge a centrifugal fan witha propeller rotating in a direction opposite to that of the fan wheel.

Another object of the invention is to rotate a propeller fan located inthe inlet of a centrifugal fan from one rotor of a prime mover whilerotating' the fan wheel of the centrifugal fan from another rotor of theprime mover, revolving in a direction opposite to that of the firstmentioned rotor.

Other objects of the invention will be apparent from the followingdescription taken together with the drawings.

The invention will now be described with reference to the drawings, ofwhich:

Fig. l is a side elevation of one embodiment of this invention; v

Fig. 2 is a sectional view along the lines 2--2 of Fig. 3;

Fig. 3 is an enlarged cross section of Fig. 1, and

Fig. 4 is an enlarged section along the lines 4-4 of Fig. 3.

The propeller blades In on the hub II are mounted in the inlet passage92 upon the solid shaft l3. blades I5 is mounted upon the hollow shaftIS. The solid shaft l3 revolves within the hollow shaft H5. The hollowshaft I6 is attached to the rotor i8 of the steam turbine indicatedgenerally by Hi, and the solid shaft i3 is attached to the m rotor ofthe turbine. The wheel M and rotor l8 rotate around the ball bearings llwhich are supported by the vertical extension 30 of the casing 28 of theturbine l9. The details of the turbine rotors and their cooperatingmechanism 15 are similar to those disclosed in my Patent No. 1,434,672,issued Nov. 7, 1922, and will not be described in detail here.

In the embodiment of the invention illustrated by the drawings, theupper end of the shaft I3 is supported by the thrust bearing 2| which isenclosed in and supported by the stream-lined hub 22. The hub 22 issupported from the wall 23 by means of the arms 24.

Thecasing 25 of the centrifugal fan is supg ported from the wall 23 asby the bolts 26 in the horizontal extension 21. The casing 28 of theturbine 69 is supported from the lower portion of the casing 25 by meansof the bolts 29.

To prevent the passage of steam from the 30 turbine it between the innershaft l3 and the outer shaft IS, the shaft l3 has attached to it justabove the uppermost bearing H, the member 30 which forms a basincontaining the mercury 3|. Attached .to the upper portion of the 5 highturbine efilciency. The rotor l8 revolves the 4;,

shaft l6 and centrifugal fan wheel in one direction while the rotor 20revolves the shaft l3 and the propeller blades ill in the oppositedirection. The propeller blades ill deliver a high velocity, whirlingair stream, axially into the inlet of the centrifugal fan wheel M. Theblades I5 of the wheel l4 revolving in opposite direction to that of thewhirling air stream delivered by the propeller blades l0, impact it athigh relative velocity providing high energy conversion and a Thecentrifugal fan wheel M with relatively high air pressure. The air underhigh pressure is delivered at the outlet ll of the involute casing 25 tobe used as desired.

The inlet passage I2 need not, of course, be an opening in a wall as inthe embodiment illustrated. The passage may be provided by a casing asis usual in the art. Likewise the centrifugal fan blades may'be curvedinstead of radial as shown, and other departures may be made by thoseskilled in the art without departing from the spirit of the invention.

What is claimed is:

1. A blower assembly comprising in combination, a centrifugal fan wheel,means forming an axial air inlet passage into the eye of said wheel,propeller blades'in said passage, a steam turbine having rotors adaptedto turn in opposite directions, means connecting one of said rotors withsaid propeller blades, and means connecting the other of said rotorswith said wheel.

2. A blower assembly comprising in combination, a centrifugal fan wheel,a fan casing for collecting and discharging the air from said.

wheel, means forming an axial ,air inlet passage into the eye of saidwheel, propeller blades in said passage, a pair of concentric shafts,means for supporting said wheel on one of said shafts, means forsupporting said blades upon the other of said shafts, a steam turbinehaving rotors adapted to turn in opposite directions, means forattaching one of said rotors to one of said shafts, and means forattaching the other of said rotors to the other of said shafts.

,amasoa 3. A blower assembly comprising in combination, a centrifugalfan wheel, a fan casing for collecting and discharging the air from saidwheel, means forming an axial air inlet passage into the eye of saidwheel, propeller blades in said passage, a pair of concentric shafts,means for supporting said wheel on one of said shafts, means forsupporting said blades upon the other of said shafts, a steam turbinehaving rotors adapted to turn in opposite directions, means forattaching one of said rotors to one of said shafts, meansfor attachingthe other of said rotors to the other of said shafts, a turbine casingenclosing said rotors, and means for supporting said turbine casing fromsaid fan casing.

4. A blower assembly comprising in combination, a centrifugal fan wheel,a fan casing for collecting and discharging .the air from said wheel,means forming an axial air inlet e intothe eye of said wheel, propellerblades in said passage, a pair of concentric shafts, means forsupporting said wheel on the outer of said shafts, means for supportingsaid blades upon the inner of said shafts, a steam turbine having rotorsadapted to turn in opposite directions, means for attaching one of saidrotors to one of said shafts, means for attaching the other of saidrotors to the other of said shafts, and means forming a mercury sealbetween said wheel and the inner of said shafts.

/ OLIVER D. H. BENTLEY.

